HHE Cardiovascular 2019 | Page 10

CARDIOVASCULAR Cardiac biomarkers: identification and innovation With candidates identified from different pathophysiological pathways, new technologies for measurement and more perspectives of data integration, transformation is occurring in the field of cardiac biomarkers Damien Gruson PhD EuSpLM FESC Department of Laboratory Medicine, Cliniques Universitaires St-Luc and Université Catholique de Louvain, Brussels, Belgium Cardiovascular diseases represent a global burden because of related high morbidity, high mortality and a significant impact on health economies. 1 We all play a role in the fight against cardiovascular diseases, and laboratory tests are important to assist clinicians in the prevention, diagnosis and prognosis of cardiovascular diseases. Heart failure (HF) is the inability of the heart to respond to the circulatory demand of the organism. The main causes of HF are hypertension and ischaemic and valvular injuries, whereas toxic, metabolic or genetic origins are less common. In addition to the initial abnormality, secondary changes occur over the course, leading to multi-organ impairment. 1,2 More than 20 million people worldwide are estimated to suffer from HF. 1,2 HF is increasing because of an ageing population, as a result of the success in prolonging survival in patients having coronary events, and the success in postponing coronary events by effective prevention in those at high risk or those who have already survived a first event. There are several forms of HF (with reduced left ventricular ejection fraction or with preserved left ventricular ejection fraction) challenging both the diagnosis and the risk estimation pathways. 1 Understanding HF and its related molecular pathways is fundamental because it allows the identification of potential new biomarkers for patients’ management and potential innovative therapeutic approaches. HF and biomarkers Most of the biomarkers with potential applications in diagnosis and prognosis derive 10 HHE 2019 | hospitalhealthcare.com from the neurohormonal response to the failing myocardium. 2,3 Neurohormonal activation plays a significant role in myocardial and multi-organ adaptations to HF. The use of biomarkers for the diagnosis of suspected HF patients is part of daily procedures and testing for B-type natriuretic peptide (BNP) and the biologically inactive N-terminal fragment (Nt-proBNP) is included in guidelines of scientific societies. Biomarkers may also fulfil complementary information for the evaluation of disease severity, prognosis estimation and for treatment selection. 1–3 Natriuretic peptides, the standard of care Natriuretic peptides are the most recognised and used biomarkers for the diagnosis and monitoring of HF. 1-3 The natriuretic peptide family features three members: atrial natriuretic peptide (ANP); BNP; and C-type natriuretic peptide (CNP). BNP is synthesised in the ventricles as a 108- prohormone undergoing a cleavage generating the C-terminal 32 amino-acid active peptide (BNP) and the inactive N-terminal fragment (Nt-proBNP). BNP synthesis and release are essentially stimulated by a ventricular stretch due to pressure or volume overload. Natriuretic peptides are sensitive markers of cardiac dysfunction and useful biomarkers to rule out HF in emergency departments and have also value for risk stratification of HF because their circulating levels show strong negative correlations with left ventricular ejection fraction and are related to the disease severity (as determined using the NYHA classification).